where the integral converges provided that \({\rm Re}(n_1)>0\) , \({\rm Re}(n_2)>0\) , and \({\rm Re}(n_1+n_2)<1\) . We analytically continue the result in \(n_1\)  and \(n_2\) , as in [1]}. Note that for the application above, this amounts to an analytic continuation in \({\bar{h}}_1\) .
